The present invention relates to a process of providing herbal extracts in cellulose derivative capsules, and more particularly, liquid herbal medicants in vegetable gelatin, hydroxypropyl methylcellulose (xe2x80x9cHPMCxe2x80x9d), or any other cellulose derivative capsules.
Herbal remedies, also sometimes referred to as phytopharmaceuticals or dietary supplements, are becoming more and more popular as alternatives to conventional pharmaceuticals. Such herbal remedies are regarded as being more naturally healthier than conventional pharmaceuticals. Throughout the world every culture has a long history of using herbs in everyday medical treatment. For example, it is known that antidepressive activity is attributed to St. John""s wort. U.S. Pat. No. 5,622,704 to Hacker proposes using a combination of Rhizoma zingiberis and Ginkgo biloba to treat anxiety. Healthy immune function is often attributed to the use of Echinacea. Thousands of well researched scientific and university studies document the efficacy of herbal remedies.
The delivery system through which an herb is ingested plays a significant role in the way and the extent to which the herb is metabolized. Previously herbs were administered as crude plant material in either capsule or tablet form. More recently powdered xe2x80x98standardizedxe2x80x99 extracts have been recognized as botanicals that deliver more and specified potency. Herbal extracts in a fixed oil base filled into gelatin capsule have received little recognition. Problems of miscibility and absorption are numerous with such systems.
It has been suggested by many pharmaceutical companies that a liquid delivery system is a superior method of administering therapeutic remedies. Yet non-lipid base liquid botanical standardized extracts in capsule form have not been available due to the problem maintaining the capsule integrity once the liquid is filled into the capsule.
Consumer demand for capsules made from vegetable sources is increasing rapidly today. This invention specifies the procedures of providing a non-lipid, liquid herbal extract in a sealed cellulose derivative capsule such as vegetable gelatin or HPMC. This technology demonstrates the unique methods and processes utilized in extraction that enable the liquid herbal extract and vegetable gelatin, HPMC, or any other cellulose derivative capsule to remain stable without degradation once the liquid is filled into the capsule.
Specifically, the present invention relates to a process for providing non-lipid, liquid-form herbal extracts in a vegetable gelatin, HPMC, or any other cellulose derivative capsule. The process includes extracting an herbal plant material with an alcohol or aqueous/alcohol to provide an aqueous alcoholic herbal extract. This aqueous alcoholic herbal extract is transferred to a liquid glycerin-based herbal extract through rotary evaporation or other condensing equipment. This transfer of solution is accomplished by adding vegetable glycerin while the water and alcohol are being evaporated. The herbal extract is maintained in solution or dispersed in the alcohol mixture. The resulting herbal extract contains a moisture content of no more than 10 percent by weight, and preferably no more than 5 percent by weight. The herb extract is then encapsulated in vegetable gelatin, HPMC, or any other cellulose derivative capsule. A selected bio-active marker compound is measured after the step of extraction and after the step of removing water and alcohol.
As discussed above, an herbal plant material is provided. The herbal material is preferably in the form of whole leaf, stem, stalk, root and the like, and is ground or cut prior to treatment. The herbal materials can be organic, cultivated, or wild. Suitable herbal materials include, but are not limited to, kava kava, echinacea, St. John""s wort, valerian root, milk thistle seed, Siberian ginseng, nettle leaf, ginkgo, gotu kola, ginkgo/gotu kola supreme, astragalus, goldenseal, dong quai, ginseng, St. John""s wort supreme, echinacea/goldenseal supreme, bilberry, green tea, hawthorne, ginger, turmeric, black cohosh, cats claw, chamomile, dandelion, chaste tree berry, feverfew, garlic, horse chestnut, licorice, eyebright, yohimbe, astragalus supreme, valerian poppy supreme, and serenity elixir. The herbal material is then extracted with an aqueous alcohol in different concentrations to provide an aqueous alcoholic herbal extract. Suitable alcohols include C1 to C3 alcohols like ethanol. Preferably, ethanol is used. The alcohol can be a co-solvent mixture such as a mixture of alcohol and water. During extraction, the herbal material is preferably percolated or macerated to facilitate extraction.
The aqueous alcoholic herbal extract is monitored for its bio-activity. As used herein, bio-activity is defined as qualitative and quantitative measurement of the marker compounds. The methodology for measuring the bio-activity may change from herb to herb. A trained Natural Products Chemist develops the methodology or uses accepted reference methodologies.
After extraction, sufficient glycerin is added to adjust the bio-activity required to complete the standardization of the formulation. Typically from 20 to 80 percent by weight of glycerin is contained in the finished product. The mixture of aqueous alcoholic herb extract and glycerin mixture is condensed or concentrated, using any one of the various condensation techniques known to those skilled in the art. For example, rotary evaporation under reduced pressure in a warm water bath at a temperature of from about 55xc2x0 to 85xc2x0 C. can be used.
The herb extract having a moisture content of less than 10 percent is then encapsulated in a cellulose derivative capsule or vegetable cellulose capsule. Suitable celluloses include, but are not limited to, hydroxylalkyl celluloses including methylcellulose, carboxymethylcellulose, hydroxypropylcellulose, and the preferred hydroxypropyl methylcellulose (xe2x80x9cHPMCxe2x80x9d). Suitable capsules are available from many sources, and sizes from xe2x80x9c00xe2x80x9d to xe2x80x9c3xe2x80x9d are preferably used. Suitable excipients may be added to the extract prior to encapsulation and may include vegetable oils, waxes, lecithin, fats, semi-solid and liquid polyols and the like. Preferably, no excipients other than lecithin are needed. Suitable encapsulation equipment is available from market suppliers such as Shionogi. Air can be eliminated from the capsules using an inert gas such as nitrogen.